Wash and dry all produce. Preheat broiler to high or oven to 500 degrees. Slice zucchini into 1/2-inch-thick rounds. Pick oregano leaves from stems; discard stems. Roughly chop leaves.

Place zucchini on a lightly oiled baking sheet. Season with salt, pepper, and 1 tsp Italian seasoning (we’ll use more later). Place under broiler and broil until softened and browned, 5-7 minutes. (TIP: Keep an eye on the zucchini—it can burn easily.) Remove sheet from broiler; adjust oven temperature to 450 degrees.

Heat a large drizzle of olive oil in a large pan over medium-high heat. Remove sausage from casings; discard casings. Add sausage to pan along with half the oregano, breaking meat into pieces with a spatula or wooden spoon. Cook until browned and no longer pink, 4-6 minutes. Remove pan from heat.

Place flatbreads on another lightly oiled baking sheet. Season with salt and pepper. Spread a thin layer of tomatoes across the tops of the flatbreads. Sprinkle with salt, pepper, and 1 tsp Italian seasoning (you’ll have some left over). Scatter evenly with mozzarella, then follow with sausage and zucchini.

Bake pizzas in oven until flatbreads are golden brown at the edges and cheese is melted, 4-6 minutes.

Scatter remaining oregano over pizzas (to taste), then cut pizzas into slices and serve.